In certain downhole operations, power is needed to run various components of a downhole assembly. For example, power is need to drive actuators for valves and other components, and to power various sensors and communication devices. In many cases, power is generated downhole via a downhole power generation device that is coupled to the downhole assembly. Some of the devices may be designed to use mechanical power from the fluid flow to generate electric power downhole such as the mechanisms using flow induced vibration, turbomachinery, and the like. However, when such power generation mechanism is designed to run continuously, it must endure a large amount of stress and wear. This leads to a short operating device life. This is a problem because maintenance of such devices is extremely difficult and often impossible, and the expected life of such devices is much shorter than the life of the well. Additionally, such power generation devices typically generate more power than is needed to carry out the functions of the downhole assembly. Thus, the stress and wear seen by the power generation mechanism in generating the excess power does not translate into increased utility.